#include "RooDataHist.h"
#include "RooDataSet.h"
#include "RooHistPdf.h"
#include "RooNDKeysPdf.h"
#include "RooRealVar.h"
#include "TH2F.h"
#include "TRandom.h"

#include <iostream>

void hist2dgenerate() {
    // make a faux dataset
    TH2F* h2 = new TH2F("h2","h2",40,-5.,5.,40,0.,10.);
    for(int i = 0; i < 10000; ++i)
        h2->Fill(gRandom->Gaus(0,2),gRandom->Exp(2));

    RooRealVar * x1 = new RooRealVar("x1","x1",-5.,5.);
    RooRealVar * x2 = new RooRealVar("x2","x2",0.,10.);
    RooDataHist* dh = new RooDataHist("dh","dh",RooArgList(*x1,*x2),h2);

    // use keys to smooth as i
    // don't want zero bins in
    // my hist pdf
    RooNDKeysPdf keys("keys","keys",RooArgList(*x1,*x2),*((RooDataSet*)dh));

    delete h2;
    h2 = (TH2F*)keys.createHistogram("h2",*x1,RooFit::YVar(*x2));
    delete dh;
    dh = new RooDataHist("dh","dh",RooArgList(*x1,*x2),h2);

    // this is my end 2d pdf
    RooHistPdf* hpdf = new RooHistPdf("hpdf","hpdf",RooArgSet(*x1,*x2),*dh);

    for(int i = 10; i <= 100; i+=10) { // number of events per toy mc
        std::cout << "\ni=" << i << " : ";
        std::cout.flush();
        for(int j = 0; j < 10000; j++) { // number of toy mc
            if (!((j+1)%1000)) {
                std::cout << j+1 << " ";
                std::cout.flush();
            }
            RooDataSet* tmp_ds = hpdf->generate(RooArgSet(*x1,*x2),i);
            RooAbsReal* nll = hpdf->createNLL(*tmp_ds);
            nll->addServer(*x1); // 5.26.x bug workaround
            double nll_val = nll->getVal();
            delete nll;
            delete tmp_ds;
        }
    }
    std::cout << std::endl;
}